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Prototype Bi-Rotor Combine Sells for $22,000

Indiana Entrepreneur has plans to update and improve upon original design, possibly take to market.

The final chapter of Mark Underwood’s dream reaper is yet to be written.

After bidding between three potential buyers, the original Bi-Rotor prototype combine sold for $22,000 at Underwood’s estate auction held near Burr Oak, Kansas, on October 29.

The XBR-2 – a built-from-the-ground-up prototype combine featuring the bi-rotor threshing system brainchild of Underwood, was acquired by Peridot, Inc., a Hoagland, Indiana, manufacturing firm.

David Hockemeyer, president of Peridot, says it is possible that the XBR-2 may live to see another day.

“We want to help the American farmer go about agriculture maybe a little more efficiently. We understand that medium to small farmers have to meet their bottom lines, and we’re going to try and help them out,” he says.

“We’re planning to continue what has been started here,” he adds. “The original Bi-rotor group did all the hard work.’

Underwood and his cousin, Ralph Lagergren, developed, built from the ground up, and field-tested the XBR-2 Bi-Rotor combine prototype in the mid-1990s before selling several of the machine’s patents to John Deere. Underwood succumbed to cancer in 2017. His estate auctioned off the XBR-2, and Whitey, a Case 1480 combine with the Bi-Rotor mechanism inside. That machine sold for $8,000.  

Underwood was in his teens when he first envisioned a combine-threshing system that used dual rotating concaves. The outside concave moved slower than the inner unit, which proved to be far more efficient and gentler on crops than conventional threshing systems. Underwood and Lagergren formed the company Agri-Technology, which built the XBR-2 and eventually sold 17 patents to John Deere in 1995.

Peridot’s plans

Peridot is a “…machine shop, 3-D printer, prototype, and product development” company, Hockemeyer says. Among its enterprises, Peridot manufactures seed plates for Kinze and John Deere planters that allows for planting small grains and cover crops.

“I’ve brought along a couple of engineers, and we’re just going to have fun with a passion that we all share, and that is agriculture. We have a business already that can make just about anything, so we’re good at making things,” he says. “Now, let’s make our own product, put our name and our stamp on it, and go from there.”

Hockemeyer’s plan is to haul the XBR-2 to Indiana, take it apart to fully understand the Bi-Rotor system and the various other innovations the XBR-2 featured, then use modern technology such as 3-D printing and 3-D Computer Aided Design to learn how the Bi-Rotor can be improved upon.

He expects a fresh perspective can breathe new life into the original Bi-Rotor, with the potential to release a version to the public.

“It’s our job to take this as a basis, maybe make it a little better, and protect it again, and come about it from a little different angle, a piece of equipment that will be very useful – year around,” he says.

Time will tell when, or even if, a new Bi-Rotor is ready for market. Hockemeyer says it will be at least three to five years. “When we come out with this thing again, it will be pretty close to being ready. But it will take some time to do it right, just like the first team did,” he says.

Ralph Lagergren and David Hockemeyer
Several members of the original Bi-Rotor team, plus a few who joined the team after the patents were bought by Deere in 1995, came to Kansas for Underwood’s estate auction. Those folks introduced themselves to Hockemeyer after the combines sold.

For his part, Lagergren (pictured at right with Hockemeyer) is ecstatic that the Bi-Rotor could be commercialized. “I hope that happens,” he says. “I couldn’t be more pleased. What could be better than if these guys actually took it to market. It could be pretty interesting.”  

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